http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
자기적 방법에 의한 0.85% 탄소강의 열처리에 따른 미세조직 및 기계적 성질 평가
변재원,권숙인,Byeon, Jai-Won,Kwun, S.I. 한국재료학회 2003 한국재료학회지 Vol.13 No.2
Microstructures and mechanical properties of variously heat treated 0.85% carbon steel(eutectoid steel) were evaluated by magnetic property measurements. Microstructural analysis (pearlite interstellar spacing), measurement of mechanical properties(Rockwell hardness, yield stress, fracture stress) and magnetic properties(coercivity, remanence, hysteresis loss, saturation magnetization) were performed to clarify mutual relationships among these parameters. Water quenched specimens with martensite structure showed much higher coercivity and remanence than air cooled or furnace cooled specimens with pearlite structure. The linear dependence of coercivity and remanence on pearlite interlamellar spacing as well as on Rockwell hardness, yield stress and fracture stress was observed in the pearlitic steel. Hysteresis loss and saturation magnetization showed no distinct trend with pearlite interlamellar spacing.
페라이트기 9Cr 내열강의 크리프-피로손상에 따른 미세조직 및 초음파 비파괴평가
김정석,권숙인,박익근,Kim, Chung-Seok,Kwun, S.I.,Park, Ik-Keun 한국재료학회 2007 한국재료학회지 Vol.17 No.8
The microstructural evolution of ferritic 9Cr-1Mo-V-Nb steel, subjected to creep-fatigue at $550^{\circ}C$, was evaluated nondestructively by measuring the ultrasonic velocity. The variation of the ultrasonic velocity with the fatigue life fraction exhibited three regions. In the first region ($N/N_f$<0.2), a significant increase in the velocity was observed, followed by a slight increase between the fatigue life fractions of $0.2N_f$ and $0.8N_f$, and then a decrease in the final region. The change of the ultrasonic velocity during creep-fatigue was interpreted in relation to the microstructural properties. This study proposes an ultrasonic nondestructive evaluation method of quantifying the level of damage and microstructural change during the creep-fatigue of ferritic 9Cr-1Mo-V-Nb steel.